staging: r8188eu: clean up camel case in odm_signal_scale_mapping()

Rename variables in odm_signal_scale_mapping() to avoid camel case.

CurrSig -> currsig
RetSig -> retsig

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220911161949.11293-3-straube.linux@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>